Publications by authors named "Jonathan R Dimmock"

A series of 3,5-benzylidene-4-piperidones, -, were prepared to evaluate the hypothesis that the placement of different groups in the ortho-location of the aryl rings led to compounds with greater cytotoxic potencies than structural analogs. The bioevaluation of - was undertaken using human Molt/4C8 and CEM cells as well as murine L1210 cells. Correlations were sought between the interplanar angles θ and θ and the cytotoxic potencies.

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Breast cancer stands out as one of the most prevalent malignancies worldwide, necessitating a nuanced understanding of its molecular underpinnings for effective treatment. Hormone receptors in breast cancer cells substantially influence treatment strategies, dictating therapeutic approaches in clinical settings, serving as a guide for drug development, and aiming to enhance treatment specificity and efficacy. Natural compounds, such as curcumin, offer a diverse array of chemical structures with promising therapeutic potential.

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Breast cancer represents a critical global health issue, accounting for a substantial portion of cancer-related deaths worldwide. Metastasis, the spread of cancer cells to distant organs, is the primary cause of approximately 90% of breast cancer-related fatalities. Despite advances in cancer treatment, conventional chemotherapeutic drugs often encounter resistance and demonstrate limited efficacy against metastasis.

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The objective of this study is to find novel antineoplastic agents that display greater toxicity to malignant cells than to neoplasms. In addition, the mechanisms of action of representative compounds are sought. This report describes the cytotoxicity of a number of dimers of 3,5-bis(benzylidene)-4-piperidones against human malignant cells (promyelocytic leukemia HL-60 and squamous cell carcinoma HSC-2, HSC-3, and HSC-4).

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There is a need for novel antiepileptic agents whose modes of action differ from those of current antiepileptic drugs. The objective of this study was to determine whether 1-diethylamino-3-phenylprop-2-en-1-one () could prevent or at least diminish convulsions caused by different mechanisms. This amide afforded protection in the maximal electroshock and subcutaneous pentylenetetrazole screens when given intraperitoneally to both mice and rats.

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Two series of novel unsymmetrical 3,5-bis(benzylidene)-4 piperidones - and - were designed as candidate antineoplastic agents. These compounds display potent cytotoxicity towards two colon cancers, as well as several oral squamous cell carcinomas. These compounds are less toxic to various non-malignant cells giving rise to large selectivity index (SI) figures.

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This study outlines a number of studies of dichloroacetic acid (DCA) and some of its derivatives. Although DCA has low cytotoxic potencies, various structural modifications are described which result in potent cytotoxins. In particular, hybrid molecules created from DCA and other bioactive molecules whose modes of action differ from DCA are particularly promising as candidate anticancer agents.

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Cancer remains the second most common cause of death in the US. Due to a recurrent problem with anticancer drug resistance, there is a current need for anticancer drugs with distinct modes of action for combination drug therapy We have tested two novel piperidone compounds, named 2608 (1-dichloroacetyl - 3,5-bis(3,4-difluorobenzylidene)-4-piperidone) and 2610 (1-dichloroacetyl-3,5-bis(3,4-dichlorobenzylidene)-4-piperidone), for their potential cytotoxicity on numerous human cancer cell lines. We found that both compounds were cytotoxic for breast, pancreatic, leukemia, lymphoma, colon, and fibroblast cell lines, with a cytotoxic concentration 50% (CC) in the low micromolar to nanomolar concentration range.

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A series of 3,5-bis(benzylidene)-1-dichloroacetyl-4-piperidones - was evaluated against Ca9-22, HSC-2, HSC-3, and HSC-4 squamous cell carcinomas. Virtually all of the compounds displayed potent cytotoxicity, with 83% of the CC values being submicromolar and several CC values being in the double digit nanomolar range. The compounds were appreciably less toxic to human HGF, HPLF, and HPC non-malignant cells, which led to some noteworthy selectivity index (SI) figures.

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Background: The incidence of cancer has been increasing worldwide. Unfortunately, the drugs used in cancer chemotherapy are toxic to both neoplasms and normal tissues, while many available medications have low potencies. Conjugated α,β-unsaturated ketones differ structurally from contemporary anticancer medications , some of which have noteworthy antineoplastic properties.

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A series of 3,5-bis(benzylidene)-4-piperidones - were prepared as candidate cytotoxic agents. In general, the compounds are highly toxic to human gingival carcinoma (Ca9-22), human squamous carcinoma-2 (HSC-2) and human squamous carcinoma-4 (HSC-4) neoplasms, but less so towards non-malignant human gingival fibroblast (HGF), human periodontal ligament fibroblast (HPLF) and human pulp cells (HPC), thereby demonstrating tumour-selective toxicity. A further study revealed that most of the compounds in series were more toxic to the human Colo-205 adenocarcinoma cell line (Colo-205), human HT29 colorectal adenocarcinoma cells (HT-29) and human CEM lymphoid cells (CEM) neoplasms than towards non-malignant human foreskin Hs27 fibroblast line (Hs27) cells.

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A novel series of 1-[3-{3,5-bis(benzylidene)-4-oxo-1-piperidino}-3-oxopropyl]-4-piperidone oximes - and related quaternary ammonium salts - were prepared as candidate antineoplastic agents. Evaluation against neoplastic Ca9-22, HSC-2 and HSC-4 cells revealed the compounds in series and to be potent cytotoxins with submicromolar CC values in virtually all cases. In contrast, the compounds were less cytocidal towards HGF, HPLF and HPC non-malignant cells revealing their tumour-selective toxicity.

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Background: Currently, a novel coronavirus found in 2019 known as SARS-CoV-2 is the etiological agent of the COVID-19 pandemic. Various parameters including clinical manifestations and molecular evaluation can affect the accuracy of diagnosis. This review aims to discuss the various clinical symptoms and molecular evaluation results in COVID-19 patients, to point out the importance of onset symptoms, type, and timing of the sampling, besides the methods that are used for detection of SARS-CoV-2.

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Background: Cancer is an ongoing worldwide health problem. Although chemotherapy remains the mainstay therapy for cancer, it is not always effective and has detrimental side effects. Here, we present piperidone compounds P3, P4, and P5 that selectively target cancer cells via protein- and stress-mediated mechanisms.

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A series of novel -acryloylhydrazides and a related series of compounds were prepared as potential chemostimulants. In general, these compounds are cytotoxic to human HCT 116 colon cancer cells, as well as human MCF-7 and MDA-MB-231 breast cancer cell lines. A representative compound -(3,4-dimethoxyphenylcarbonyl)--acryloylhydrazine sensitized HCT 116 cells to the potent antineoplastic agent 3,5-bis(benzylidene)-4-piperidone , and also to 5-fluorouracil.

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This review outlines the discovery and development of a novel series of 1-[4-2- aminoethoxy)phenylcarbonyl]-3,5-bis-(benzylidene)-4-piperidones (5-8) as potential drug candidates over the last 15 years in our laboratory. Many of these compounds demonstrate excellent cytotoxic properties and are often more potent than contemporary anticancer drugs. Two highly important features of many of these molecules are first, the greater tumour-selective toxicity and second, the ability of these molecules to act as modulators of multi-drug resistance.

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Histones are the main structural proteins of eukaryotic chromatin. Histone acetylation/ deacetylation are the epigenetic mechanisms of the regulation of gene expression and are catalyzed by histone acetyltransferases (HAT) and histone deacetylases (HDAC). These epigenetic alterations of DNA structure influence the action of transcription factors which can induce or repress gene transcription.

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A novel class of hybrid molecules 2a-o was designed as candidate antineoplastic agents from dichloroacetic acid which is a known inhibitor of pyruvate dehydrogenase kinase and a number of cytotoxic 3,5-bis(benzylidene)-4-piperidones 1. In general these new hybrid molecules are potent cytotoxins towards human HCT116 colon cancer cells. A number of lead molecules emerged having the IC values in the double digit nanomolar range.

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Conjugated α,β-unsaturated ketones are very useful compounds associated with diverse medicinal properties. This review outlines α,β-unsaturated ketones as candidate cytotoxic agents which affect mitochondrial function. Both naturally occurring compounds and synthetic chemicals have been discussed which exert their cytotoxic effects, at least in part, by acting on mitochondria.

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Background: Cancer continues to be the major health burden worldwide. There is an urgent need for the development of novel antineoplastic compounds to treat this devastating condition. Various alkylating anticancer drugs have been employed in the clinic for treating cancers.

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Purpose: Previously, compounds containing a piperidone structure have been shown to be highly cytotoxic to cancer cells. Recently, we found that the piperidone compound P2 exhibits a potent anti-neoplastic activity against human breast cancer-derived cells. Here, we aimed to evaluate two piperidone compounds, P1 and P2, for their potential anti-neoplastic activity against human leukemia/lymphoma-derived cells.

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This study aims at investigating the cytotoxicity and some of the modes of action of 3,5-bis(3-dimethylamino-4-hydroxybenzylidene)-4-piperidone trihydrochloride 3 and two related compounds 2 (which lacks the dimethylaminomethyl groups) and 4 (which has an additional dimethylaminoethyl substituent in both aryl rings) in order to ascertain the contribution of dimethylaminoethyl substituent to bioactivity. The bioactivities of 2-4 were compared with curcumin 5. Both 2 and 3 displayed submicromolar GI values towards HCT-116 cells and were significantly more potent than 4, 5 and 5-fluorouracil (5-FU).

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Novel cytotoxins 3-5 containing the 1,5-diaryl-3-oxo-1,4-pentadienyl pharmacophore are disclosed. The compounds in series 3 and 5 have the potential to liberate niacin which may reduce some of the side effects of antineoplastic compounds. 3a-c emerged as the most potent cytotoxic compounds with IC values in the low micromolar range against human Molt4/C8 and CEM CD T-lymphocytes as well as murine L1210 leukemia cells.

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Background: A novel series of structurally divergent 1,5-diaryl-3-oxo-1,4-pentadiene analogues - displayed marked cytotoxic potencies towards a number of human leukemia/lymphoma cells.

Objective: To identify novel selective cytotoxic compounds that induce apoptosis.

Methods: The Differential Nuclear Staining (DNS) screening protocol was utilized to measure the cytotoxicity of all experimental dienones on several cancerous cells.

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1-[4-(2-Alkylaminoethoxy) phenylcarbonyl]-3,5-bis(arylidene)-4-piperidones are a novel class of potent cytotoxic agents. These compounds demonstrate low micromolar to submicromolar IC50 values against human Molt 4/C8 and CEM T-lymphocytes and murine leukemia L1210 cells. In this study, a comparative QSAR investigation was performed on a series of 3,5-bis (arylidene)-4-piperidones using different chemometric tools to develop the best predictive models for further development of analogs with improved cytotoxicity.

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